array_walk_recursive
(PHP 5, PHP 7, PHP 8)
array_walk_recursive — Apply a user function recursively to every member of an array
Description
Applies the user-defined callback function to each
element of the array. This function will recurse
into deeper arrays.
Parameters
-
array -
The input array.
-
callback -
Typically,
callbacktakes on two parameters. Thearrayparameter's value being the first, and the key/index second.Note:
If
callbackneeds to be working with the actual values of the array, specify the first parameter ofcallbackas a reference. Then, any changes made to those elements will be made in the original array itself. -
arg -
If the optional
argparameter is supplied, it will be passed as the third parameter to thecallback.
Return Values
Returns true on success or false on failure.
Examples
Example #1 array_walk_recursive() example
<?php
$sweet = array('a' => 'apple', 'b' => 'banana');
$fruits = array('sweet' => $sweet, 'sour' => 'lemon');
function test_print($item, $key)
{
echo "$key holds $item\n";
}
array_walk_recursive($fruits, 'test_print');
?>
The above example will output:
a holds apple b holds banana sour holds lemon
You may notice that the key 'sweet' is never displayed. Any key that holds an
array will not be passed to the function.
